Total depth after etching is 15.651 um
Calculated remaining resist as 8.08um, indicating an erosion of 0.66um in 10 minutes of etching
This equates to an erosion rate of 66 nm/min
The etch depth of 7.57um in 10 mins indicates an etch rate of 757.0nm/min
The selectivity is therefore 11.47:1